In general, when a lesion such as stenosis or occlusion occurs in a lumen of the body such as the esophagus, the duodenum, or the bile duct, the inherent function of the lumen that moves bodily fluids is deteriorated.
A bending-retaining coated stent capable of retaining a bending state is known, wherein the stent is configured with a plurality of rhombic openings that are formed by weaving different shape-memory alloy wires alternatively with a plurality of interlocking portions and a plurality of intersection portions such that the rhombic openings are changeable in size by an external force, and which is subjected to heat treatment to memorize a shape thereof. Then, a polytetrafluoroethylene (PTFE) tape or a similar material is wound around a plurality of sections divided in a lengthwise direction of the stent with an interval so that a coating layer of silicone or a similar material is prevented from being coated on the interlocking portions and the intersection portions comprised of the stent wound with the tape, and on the rhombic openings formed thereby. Accordingly, the interlocking portions, the intersection portions, and the rhombic openings that remain uncoated are allowed to freely change in size by an external force, thereby maintaining a bending state.
However, this stent is problematic in that the coating layer made of silicone or the like on the outside of the stent may slide at the lesion such as stenosis or occlusion due to movement of the human body or an external force.